I'm trying to install Oracle Database XE 18c on Oracle Linux 8.1 and here's what I get:
As you can see, it's missing oralce-database-preinstall-18c. Naturally, I've tried to install it as described in several tutorials (including this one):
But it didn't work. Then I've tried to install these missing packages and after that install preinstall package, but it didn't work, they're still missing.
How it could be fixed?
Oracle Database can't be installed on Oracle Linux 8 (yet) so there is no preinstall RPM for Oracle Linux 8 yet either. What you're trying to do isn't possible. Please reinstall using Oracle Linux 7 if you want to install Oracle Database.